I think I'll stay aps-c a bit longer than planned. Certainly this should put pressure on Canon to become more innovative in the lens arena. Even more considering Sigma's success with their new 35mm f/1.4.

Judging from the way other ultra-large-aperture zooms are designed (e.g. the Oly 35-100 f/2) I'd guess that the design is basically a 35-70 f/3.5 with a reversed 2x teleconverter at the back.

I imagine that an FF version of this concept would weigh well north of a kilogram (& cost well north of a kilobuck).

Kudos to Sigma for being innovative once again. Hopefully this will show C & N that there's real demand for more large-aperture lenses.

I've said this before and I'll say again, do we really mind a 1.4 kg lens that covers 24-70 at f1.8? We carry the 70-200 with that weight with no issues, so why not a 24-70?

I think there would be problems in doing a sharp lens with those features. If you look at the MTF charts for this Sigma it's clear that border performance suffers quite a bit wide open - and it's only a 15 MP APSC.

Good size comparison to give you an idea of size and weight with something you might be familiar with, but not a fair lens comparison...the Canon is for FF cameras..not just APS-C. Still... A very exciting lens! I have the new 35mm f/1.4 and it ROCKS!Can't use this one though as I am a FF user...but I hope the specs are incredible....I want the whole Art Line to be fantastic!